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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Potential and problems related to reuse of water in households /

Eriksson, Eva Helena. January 2002 (has links) (PDF)
Thesis (Ph. D.)--Technical University of Denmark, 2002. / Includes bibliographical references (p. 38-41). Also available in electronic format via Internet.
12

Sustainability and water resources management for the northern Adelaide Plains, South Australia /

Fleming, Nicholas S. January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 1999? / Includes bibliographical references (64 p. ).
13

Dynamic games and competition for water resources /

Nakao, Megumi. January 2003 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2003. / Typescript. Includes bibliographical references (leaves 155-162).
14

An analysis of water resource conflict and cooperation in Oregon between 1990 and 2004 /

Fesler, Kristel J. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 94-99). Also available on the World Wide Web.
15

Water footprint of growing vegetables in selected smallholder irrigation schemes in South Africa

Nyambo, Patrick January 2014 (has links)
Knowledge of water use, through water foot printing (WF) in smallholder agriculture crop production is the key to the global fight against poverty, achievement of food security and sustainability within the world’s rural community. Water footprint of a crop can be defined as the volume of fresh water used to produce a certain crop in all the steps in the production line. This study, therefore aimed at contributing towards improvements in rural livelihoods by raising awareness of the increased productive use of green, blue and grey water in smallholder agriculture in South Africa. This was done through determination of water footprints of five vegetable crops, i.e. potatoes (Solanum tuberosum), tomatoes (Solanum lycopersicum), dry beans (Phaseolus vulgaris), cabbage (Brassica oleracea spp) and spinach (Spinacia oleracea) in the 2000-2013 period. Quantification of water footprints has been done worldwide but, in South Africa (SA) focus has mostly been on the industrial and domestic sector. Water footprint assessment framework, was used to estimate the full impact of vegetable production on water resources at Zanyokwe, Thabina and Tugela Ferry irrigation schemes as case studies. The CROPWAT@ model was used to calculate crop evapotranspiration, differentiating green and blue water. Local climatic data were obtained from SA weather services, while the crop and soil parameters were obtained from the FAO data base. Nitrogen was considered the main pollutant hence its use in the grey water footprint calculation. Generally, Thabina irrigation scheme had the highest water footprint, followed by Tugela Ferry irrigation scheme whilst Zanyokwe irrigation scheme had the lowest. Green beans had the highest water footprint at all the three irrigation schemes with Thabina irrigation scheme having the highest (3535.1 m3/ton). For Tugela Ferry irrigation scheme, the calculated WF was 2753 m3/ton whilst the lowest was observed at ZIS i.e. 2407.6 m3/ton. Cabbage had the lowest water footprint. The highest water footprint for growing cabbage was 254.5 m3/ton in TFIS, 223.1 m3/ton in TIS and the lowest was 217.8 m3/ton in ZIS. The differences observed in the WF of a crop at each scheme maybe attributed to the differences management, weather and environmental characteristics, in the three locations. Moreover, the needs for ET are related to soil type and plant growth, and primarily depend on crop development and climatic factors which are closely related to climatic demands. The grey water footprint was calculated using the recommended fertilizer application rates for all the three sites. Green beans had the highest WFgrey i.e. 373 m3/ton and the lowest was cabbage with 37 m3/ton. Potato, spinach and tomatoes had 156 m3/ton, 214 m3/ton and 132 m3/ton, respectively. Grey water footprint in this study was higher as compared to other studies, possibly because of the high rates of nitrogen fertilizers used in the calculations and the low yields farmers get. Compared with estimates from other studies, the water footprints of vegetable production within smallholder irrigation schemes was relatively high. There is therefore, a need to focus on crop management and tillage practices that will help in increasing yield while minimizing water usage.
16

Is Increased Water Consumption Among Older Adults Associated with Improvements in Glycemia?

Clark, Adrienne G. 26 May 2013 (has links)
The high rates of obesity and impaired glycemia in older adults place these individuals at risk for developing diabetes. Dehydration, glucose tolerance, and insulin resistance are related. Many older adults do not achieve the Dietary Reference Intake (DRI) for water, and aging and dehydration are both associated with decreased glucose tolerance. Conversely, weight loss is associated with improvements in glucose tolerance. For older adults following a hypocaloric diet, additional water consumption may lead to greater weight loss. Furthermore, research suggests an association between insulin resistance and arginine vasopressin (AVP), the hormone responsible for regulating body water retention. Analysis of the association between plasma copeptin (an AVP derivative) and fasting glucose, insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) may provide further insight into the relationship between dehydration and diabetes risk. To our knowledge, few investigations have addressed this relationship between dehydration, impaired glycemia, and insulin resistance and how increasing water consumption may influence diabetes risk. Our purpose was to investigate the possibility that increased water consumption among older adults (n=29, BMI=31+1 kg/m2, age=62+1 years) could improve glycemia beyond that observed with weight loss, as well as associations between plasma copeptin and diabetes risk. Analysis of diabetes-related variables for subjects grouped according to study intervention group, amount of drinking water consumed, or pair-matched for weight loss and gender did not reveal significant differences between groups. Improvements in fasting insulin for water group participants, as well as correlations between hydration and insulin resistance support the need for future investigations. / Master of Science
17

Applying gamification to raise awareness of an individual’s water consumption

Hossain, Samina January 2022 (has links)
Water is essential to life, but it is becoming inadequate, even in Europe. In central, western, and a few parts of northern and northeastern Europe, water availability is facing challenges due to the impacts of climate change. These impacts further cause strains on water abstractions needed for agriculture, industries, energy, and public water supply, as well as causing extreme weather conditions like droughts during the summer. One possibility is to reduce these issues by raising awareness among individuals of their direct and indirect water consumption. However, this study implies that people cannot visualize their water consumption due to not possessing or conveniently accessing their water meter. Thus, this thesis explores the implementation of gamification and its features using a prototype to observe if this can create motivation to educate individuals in reducing their water consumption. This study uses research through design approach centered around the mid-fidelity mobile application prototype, named SAVR, developed in the iterative design process. The iterative process consists of three phases where the participants are involved in evaluating the prototype containing gamification features. The results suggest that specific game features such as points, progress and feedback successfully engaged participants in using the prototype, consequently changing their attitude, and stimulating some awareness raised on their water consumption. Overall, this opens a scope for municipalities to adopt a gamified mobile application to communicate the importance of sustainable water use as well as educating the citizens of the awareness in a playful way.
18

Quantifying the life cycle water consumption of a passenger vehicle

Tejada, Francisco Javier 06 April 2012 (has links)
Various studies have pointed out the growing need to assess the availability of water sources in regions around the world as future forecasts suggest that water demands will increase significantly for agricultural, industrial and human consumption while freshwater resources are being depleted. One such emerging issue is the effect of industrial operations on said resources, specifically from automobiles. With numerous localities experiencing stresses on water availability, key stakeholders - suppliers, automakers, and vehicle end-users - need to better realize the effect vehicle manufacturing, usage, and disposal have on water resources. While efforts to improve the overall environmental performance of vehicles have mainly concentrated on improving technologies, there has also been considerable effort devoted to characterizing the life-cycle performance of the vehicle product system. However, much of this work has focused on energy consumption and carbon emissions while few studies have examined water. The difference between water use versus water consumption were highlighted and the life-cycle water consumption of a gasoline-powered midsize vehicle were analyzed from material extraction through production, use, and final disposition/end of life. This analysis examines each of the phases to determine a carâ s water footprint using data from the EcoInvent Life Cycle Analysis database as well as data collected from literature sources. Although water use is typically metered at the factory level, water consumption (i.e., water lost through evaporation and/or incorporation into a material, part, and/or product) is much harder to quantify. As shown in this thesis, the difference can be an order of magnitude or more because much of the water that goes into the different processes is either reused, recycled, or discharged back to its original source. The use phase of a vehicle has the biggest impact on the overall vehicle water consumption, followed by material production, whereas water consumption for the end of life processing seems to be relatively insignificant. It is also shown that the impact of energy consumption as part of the total water footprint is very large when compared to the other processes given the dependence on water for energy production. The assessment in this thesis represents a life-cycle inventory and serves as an initial benchmark as no previous study has been completed to determine the water consumption for the life of a vehicle, let alone for most other products. The impact of water consumption varies by region and locality, and a differentiation of impact would still be needed to determine whether the water consumption actually happens in water scarce regions or not.
19

A conceptual end-use model for residential water demand and return flow.

Jacobs, Heinz Erasmus 27 May 2008 (has links)
A conceptual end use model for residential water demand and return flow is presented in this thesis. The model requires a unique description of a single residential stand in terms of all its end-uses. The end-uses include toilet flushing, bathing and showering, garden watering, leaks, et cetera. Various parameters describe each of the end-uses. The model predicts five components relating to water demand and wastewater flow at a residence: indoor water demand, outdoor water demand, hot water demand, wastewater flow volume and concentration of solutes in the wastewater. Twelve monthly results are calculated, for each of the five components, to provide a typical seasonal pattern as well as an annual value. The large number of input parameters in an end-use model allows for powerful and detailed analysis. The parameters required to populate the model are discussed and guideline values are presented. The end-use model is used to conduct a sensitivity analysis of each independent parameter for each of the five individual model components. The elasticity and sensitivity is determined at a base point with respect to each parameter for all five results. A research significance index is also devised to integrate the elasticity and availability of data for each parameter. The result is a prioritised list of the most critical parameters for each of the five components, which are the ones that should receive the focus for future study and data recording. The parameters are combined to obtain a list of the overall most important parameters in the model for all components combined, and based on a combination of the elasticity-based rank and the sensitivity based rank. The five most important parameters are the household size, toilet flush frequency, toilet flush volume, the washing machine event frequency and the volume of leaks on a stand. The practical application of the model is illustrated. The researchers first apply the model to mimic a few commonly accepted characteristics of water demand. The effectiveness of some specific water demand management measures are evaluated by adjusting selected model parameters. The measures include xeriscaping, the installation of dual-flush toilets, low-flow showerheads, pool ownership and pool cover use. The model also enables practitioners to obtain an insight into the water use habits of homeowners. The model forms the basis for further research work in the field. Its relatively simple structure and realistic data requirement encourages its integration into existing commercially available software suites for water and sewer system analysis and -management in the civil engineering industry in South Africa, as well as abroad. / Prof. J. Haarhoff
20

Estimating Residential Water Demand: a Case of Multiple-Part Tariff for Denton, Texas

Wattanakuljarus, Voravit 12 1900 (has links)
This paper analyzes the demand for water in case of a multiple-part tariff in Denton, Texas. The model used is developed from Billing & Agthe's model by using the following variables: marginal price, difference variable, tax assessed value, lot size, house size, temperature and rainfall.. The results indicate that temperature has the greatest effect on water demand, since this area is considered to be a very warm area. Also, marginal price seems to have a strong effect on water consumption indicating that customer is well-informed to a change in rate schedule. This test supports the original idea of the previous articles that the coefficient on difference variable and that on income should have the opposite sign. However, this test can not prove that those coefficients should be equal in magnitude, since the proxy of the income variable can not represent the individual monthly income. In addition, this article introduces another variable which can be a proxy of outdoor water use. That is lot size showing the effect on water demand. The last variable used in the model, house size,does not have much effect on water demand and is dropped out in the final model.

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